Method of making milker pails



Jan. 16, 1951 F. J. J. J. HENRARD 2,538,093

METHOD OF MAKING MILKER FAILS Filed Dec. 11, 1948 2 Sheets-Sheet 1 awgywfig/wwz Y W ya.

1951 F. J. J. J. HENRARD 2,538,098

METHOD O MAKING MILKER FAILS Filed Dec. 11, 1948 2 Sheets-Sheet 2 Patented Jan. 16, 1951 METHOD OF MAKING MILKER PAILS Fernand J. J. J. Henrard, Remicourt, Belgium, assignor to Babson Bros. 002, a corporation of Illinois Continuation of application Serial No. 648,112, February 16, 1946. a This application December 11, 1948, Serial No. 64,754

8 Claims. (Cl. 29148.2)

This invention relates to a method of making milker pails, and more particularly milker pails of the suspended type.

This application is a continuation of my application Serial No. 648,112, filed February 16, 1946, now abandoned.

Suspended milkers, as of the type shown in McCornack Patent 1,859,213, make use of a pail of substantial diameter with a lid opening of less than half such diameter, and with a height of the same order. For example, a commercial suspended milker now being sold on the market uses a pail with a diameter of about inches, a maximum height of about 7 inches, and an opening in the top portion with a diameter in the neighborhood of 7 inches. In usage this opening is closed by a lid sealed vacuum tight to the pail, the lid having connector nipples for the milker inflations and also carrying the pulsator and its connections. The general construction and operation of a milker of this type is well known and will not be described further.

All milkers of the suspended type heretofore made have involved the use of a seam of the overlapping type between upper and lower sections of the milker pail. That is, the milker pail normally comprises an upper part made in one draw or series of draws, at least in one forming operation; and a lower part separately drawn or formed. l-Ieretofore the parts have been so arranged that adjacent edges overlapped and the resultant seam was then spot welded or otherwise fastened. A small collar or annulus was then usually welded on around the neck portion or opening to provide a horizontal upper surface adapted to receive the lid. The seams thus formed were undesirable, not so much in' that they spoiled the appearance of the milker pail, although this was to some extent the case, but primarily because they provided a lodging place for bacteria which could not readily be washed out in the usual washing and sterilizing operation of the milking equipment. Any such pocket or focal point of bacteria, of course, tends to contaminate new milk at each milking with undesirable results in the way of a higher bacterial count, reducing its value at the milk station, etc.

All conventional methods of making a butt welded construction have heretofore failed with a pail of this type, in view of the relatively small opening in the upper part of the pail, which prevented any support or registry of the pail parts interiorly by previous conventional methods.

I have devised a new supporting apparatus for and method of welding milker pail partstogether which overcomes these previous difliculties and objections, and which makes what .is for all practical purposes a seamless pail, a pail made in accordance with my inventions having completely smooth inner and outer walls which not only have the desirable appearance of seamless construction, but which also completely avoid any chance of unwashable pockets on the inner surface of the seam.

Other features and advantages of my inventions will be apparent from the following specification, and the drawings, in which:

Figure 1 is a top View, partly broken away, of the two main pail parts with supporting apparatus therein for use during welding; Figure 2 is a transverse sectional view along the line 2-2 of Figure 1; Figure 3 is a partial enlarged elevational view of the pressure applying portion of the supporting apparatus, along the line 3-3 of Figure 1; Figure 4 is a plan view of apparatus used in rolling the welded seam, with a pail shown in place therein; Figure 5 is a side elevational View of the apparatus shown in Figure 4; Figure 6 is a transverse sectional view of the supporting apparatus used interiorly of the pail during welding, along the line 6-6 of Figure 1; and Figure 7 is a cross sectional view similar to Figure 6 but of supporting apparatus used during rolling of the seam.

The essential features of my invention are rolling of the welded seam from the outside with substantial pressure to eliminate non-uniformities, supporting the seam interiorly during such rolling, and supporting the adjacent edges of the upper and lower pail parts interiorly during welding. While these inventions may be employed for use in various types of apparatus, so that it will be understood that variations and changes are contemplated so long as they come within the scope of the appended claims, I am describing only a single preferred method of and apparatus for achieving the desired pail construction.

. In the particular embodiment of my invention illustrated herewith, a milker pail ID is shown as having main upper and lower parts [00, and lflb. The specific curvatures and relations of these parts may, of course, be varied to secure any finished pail desired; and the upper part would have a rim or annulus welded to the neck portion Illa around the opening II together with a handle, and the lower part may have a supporting ring welded or otherwise fastened to the bottom thereof, as desired, to complete the finished pail, none of these parts being shown since they have no connection with the present invention, except that the seam between the neck portion iiia and the annulus or ring part fastened thereto may be accomplished in a manner similar to that which will be described for the main seam between the two parts its and H31) of the milker pail.

Within the milker pail is supporting apparatus comprising as its principal parts the two sector members l2 and 53. These two parts are separately but pivotally connected together at one end, as by use of a pin it in :cooperatinggrooves or recesses in the adjacent ends of the sector parts; and are adapted to be separated or moved apart by actuating means at their other ends.

This actuating means comprises a wedge-like member 15 adapted to cooperate with angularly disposed edges on the cooperating ends of the sector members l2 and it, as may be best seen in Figure 3. A bridging member 56 is adapted to 'span the opening between the sector members beneath the wedge 'mernber l5; and astud H provides threaded means for pulling the wedge down (as the stud is rotated by a wrench) to force these ends of the sector members apart. The sector members are so formed that the outer or arcuate surfaces thereof have curvatures conforming, in expanded position, to the interior curvature of the pail adjacent the seam, the wedging member He being provided witha curved edge engaging thepail wall and completing 'sup .port for the inner surface of the wall completely around the pail body adjacent the seam.

.As may be best seen in Figure 6, at least the outersurface of the sector members is composed of .copper, this being shown in Figure 6 as an additional piece lZa on a steel body portion I21) of the sector member 52, although it will be understood that other materials may be used. This .outer surface of thesector member is provided with .a central depression or groove identifiedas -l'2'a' in Figure 6. This groove isdesigned v.to register with the junction of the edges of the upper and lower parts of the pail body during welding-of the seam, as may be best seenin Figure .2. Engagement of the supporting member with the inner walls above and below this June-- tion line ensures perfect registry and maintenance of position during welding; while the groove permits heat to be developed locally at the joint and any small local expansions to take place. Maintenance :of the inner supporting apparatus at the proper height above the bottom :of the pail is ensured by the provision of spacer,

means on each member, as for example the legs -.l8a--c on the sector member l2 and the corresponding legs 5911-0 on the sector member 13.

After the seam has been welded it comprises :a portion which is generally somewhat thicker "than the adjacent portions of the wall on each side, and which has local irregularities in the way of bumps and depressions. Ihave found that .if the :joint is supported interiorly of the pail-and rolled under substantial pressure applied exteriorly, the metal at the welded seam can be worked so as to eliminate these irregularities and result in a wall thickness and smoothness at the seam corresponding to that of the material on each side, so that when the seam is buffed the pail is apparently of onepiece construction with no seam whatsoever. This'is particularly true where the stainless steel forming the preferred pail walls is butt welded by the atomic hydrogen method, without the Iing "then as shown in Figure 2.

use of any additional filler material, so that all material at the joint is stainless steel.

One method of readily rolling the joint while applying the very substantial pressures necessary is shown in Figures 4 and 5. The rolling apparatus there disclosed comprises a base 20 on "which is rotatably mounted a supporting table 2| adapted to receive the pail l0. symmetrically spaced about the table 2| are mounting brackets :22, 23 and-24 supporting rollers 25, 26 and 21,

the spacing of the parts being such that when the milker pail is on the supporting table the middle of the "outer surface of each of the rollers bear against the welded seam, as may be best seen infigurefi. Each roll preferably is of hardened steel and :formed with a very slight divergence from its center line, as for example by having its surface taper back from its center line to each side at about 1 divergence inward from a line through the outer surface parallel to the axis'of the roller.

In order to apply the necessary pressure and effect the rolling working of the welded seam rapidly, one roll, as the roll 26, is slidably mounted in its mounting bracket, and adapted to be forced inwardy toward the pail by operation of some "threaded means, as the stud 28 threaded into a fixed part of the bracket 23 and bearing :against a slidable roll-carrying block 29. One "of the rolls is preferably power rotated, this being shown as the roll 21 operated through suitable reduction gearing comprising the gear 30 and pinion 31 by the motor32'.

During this rolling operationthe welded seam is supported interiorly by a supporting arrangement which is analogous to that shown and described in more detail heretofore, except that the cross section of the outer .surfaceof the sector members is somewhat different, as may be seen in Figured. Here the :sectormember 42 (correspondi g, for example, to the sectormember I2 in general construction) comprises a .solid steel bodyportion having at least the outer, surface thereof hardened. Even more important, the outer surface has a straight central portion .42a.and slightly inwardly diverging side portions 42b and 420. The central portion may, for .examplejhave a width of about inch; and the side portions may each .well be in theneigh- .borhood of inch long (speaking of the cross section) andpreferably diverge at a very small angle, as 1. This shape of the inner supporting means, inconjunction withthe shape of therolls, provides a working effect immediately at the seam which issubstantially unimpeded .by engagement with portions of the pail wall more than a-small fraction of an-inch on each side of the seam.

Assuming that the upper and lower pail sections have been properly formed,.as by drawing,

from stainless steel, .thesupporting apparatus of the type shown in Figures 1-6 would beiplaced in the lower portion and'the upper 'portion then "placed thereover, with the wedging portion 15 lying immediatelybeneath the opening I l .in the upper part of the pail. A socket Wrench or the like would then be used to'rotate the stud H and wedge apart the sector members :to provide a firm grip .or support entirely aroundthe inner walls adjacent the seam line, the situation be- The adjacent edges of the stainless steel parts would then be butt welded, preferably by the atomic hydrogen procedure, and then 'the stud H would be rotated back until it was threaded out of the bridge member I6, whereupon the wedge portion I5 would be lifted up out of the opening. One sector member and then the other would then be brought up out through the opening I I, this being a very easy and simple procedure once the sector members are separated. The bridge member I6 would then be picked up out of the pail and, if it is a loose piece, the pin [4, although this pin may well be spot welded or otherwise fastened to one of the sector members. Sector members having a cross section of the type shown in Figure 7 would then be inserted through the opening and maneuvered into a position corresponding to that of the sector members used to support the pail walls during welding, whereupon a wedge piece, bridge and stud would be inserted, threaded together, and the stud drawn up with a wrench to force these latter supporting members into tight engagement with the inner wall at the seam, entirely therearound. The pail with this latter supporting means would then be placed on the rolling apparatus, as shown in Figures 4 and 5, and a wrench or other means used to draw up the roll 26 into tighter and tighter engagement with the outer wall of the seam as the motor 32 drove roll 21 to rotate the milker. Because of the symmetry of the roll arrangement, drawing up on the one roll is sufiicient to result in a uniform rolling pressure of all three rolls of any amount desired, preferably of at least several hundred pounds. I find it desirable to use relatively high rolling pressure and only to rotate the pail two or three times under high pressure, as continuous rolling and rerolling of the seam at lower pressures sometimes causes a hardening which renders it impossible to make the seam thickness uniform with that of the walls on either side.

After the rolling has been properly completed the stud 28 would be backed off, the stud 41 loosened and the supporting parts removed from the pail as described before. The neck flange (not shown) would then be welded in place and this seam also rolled, either with an internal support analogous to that just described or by use of cooperating inner and outer rolls, since the full opening area is available. The main or central seam presents the greatest problem because the diameter of the milker is normally, at this point, two to three times the diameter of the opening I I, so that any conventional apparatus or method for working or rolling a plate or seam is not usable.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many. modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims.

I claim:

1. A method of making sta nless steel mi ker pails of the suspended type, comprising drawing sheet metal to form the lower part of the pail with an imnerforate bottom and generally cylindrical relatively short upstanding walls, drawing sheet metal to form the u per part of the pail with a to and generally cylindrical relatively short depending walls, providing an o ening in said top of a diameter not exceeding half that of the pail, abutting the edges of the walls of the two parts, engaging a first collapsible supporting member having an engaging surface of good heat conductivity with the inner surface of the pail walls in an area lying above and below the abutment line throughout substantially its entire peripheral length to ensure perfect registry and maintenance of position during welding, buttwelding the parts together at the abutting edges, engaging a second collapsible supporting member having a hard engaging surface with the inner portion of the welded seam throughout substantially its entire peripheral length and rolling the welded seam with high rolling pressure and a low number of rerolling traverses to avoid substantial hardening and to thereby make the seam thickness substantially uniform with that of the walls on either side.

2. A method of making stainless steel milker pails of the suspended type, comprising drawing sheet metal to form the lower part of the pail with an imperforate bottom and generally cylindrical relatively short upstanding walls, drawing sheet metal to form the upper part of the pail with a top and generally cylindrical relatively short depending walls, providing an opening in said top of a diameter not exceeding half that of the pail and substantially entirely to one side of the center thereof, abutting the edges of the walls of the two parts, engaging a first collapsible supporting member having an engaging surface of good heat conductivity with the inner surface of the pail walls in an area lying above and below the abutment line throughout substantially its entire peripheral length to ensure perfect registry and maintenance of position during welding, said supporting member having an annular groove therearound in registry with said abutment line, butt-welding the parts together at the abutting edges, engaging a second collapsible supporting member having a hard engaging surface with the inner portion of the welded .seam throughout substantially its entire peripheral length and rolling the welded seam with high. rolling pressure and a low number of rerolling traverses to avoid substantial hardening and to thereby make the seam thickness substantially uniform with that of the walls on either side.

3. A method of making stainless steel milker pails of the suspended type. comprisin drawing sheet metal to form the lower part of the pail with an imperforate bottom and generally cylindrical relatively short upstanding walls, drawing sheet metal to form the upper part of the pail with a top and generally cylindrical relatively short depending walls, providing an opening in said top of a diameter not exceeding half that of the pail, abutting the edges of the walls of the two parts, engaging a first collapsible supporting member having an engaging surface of good heat conductivity with the inner surface of the pail walls in an area lying above and below the abutment line throughout substantially its entire peripheral length to ensure perfect registry and maintenance of position during welding, buttwelding the parts together at the abutting edges, engaging a second collapsible supporting member having a hard steel engaging surface with the inner portion of the welded seam throughout substantially its entire peripheral length and rolling the welded seam with high rolling pressure applied at three spaced points and a low number of rerolling traverses to avoid substantial hardening and to thereby make the seam thickness substantially uniform with that of the walls on either side.

4. A method of making stainless steel milker pails of the suspended type, comprising drawing with a top and generally sheet metal to form the lower part of the pail with an imperfor-ate bottom and generally cylindrical relatively short upstanding walls, drawing sheet metal to form the upper part of the pail with a top and generally cylindrical relatively short depending walls, providing an opening in said top of a diameter not exceeding half that of the pail and substantially entirely to one side of the center thereof, abutting the edges of the walls of the two parts, engaging a first collapsible supporting :member having an engaging surface of good heat conductivity with the inner surface of the pail walls in an area lying above and below the abutment line throughout substantially its entire peripheral length to ensure thereby make the seam thickness substantially uniform with that of the walls on either side.

5. .14. method of making stainless steel milker pails of tr suspended type, comprising drawing stainless steel sheet metal to form the lower part of thepail with an imperforate bottom and gen .erally cylindrical relatively short upstanding walls, drawing stainless steel sheet metal to form the upper part of the pail with a top and generally cylindrical relatively short depending walls, providing an opening in said top of a diameter not exceeding half that of the pail and substantially entirely to one side of the center thereof, abutting the edges of the walls of the two parts, engaging a first collapsible supporting member having an engaging surface of good heat conductivity with the inner surface of the pail walls an area lying above and below the abutment line throughout substantially its entire peripheral length to ensure perfect registry and maintenance of position during welding, said supporting memher having an annular groove therearound in registry with said abutment line, butt-welding the parts together at the abutting edges by atomic hydrogen welding, engaging a second collapsible supporting member having a hard steel engaging surface with the inner portion of the welded seam throughout substantially its entire peripheral length and rolling the welded seam with high rolling pressure applied at three spaced points and a low number of rerolling traverses to avoid substantial hardeningand to thereby make the seam thickness substantially uniform with that of the walls on either side.

6. A method of making milker pails of the sus pended type, comprising drawing hard sheet metal to form the lower part of the pail with an imperforate bottom and generally cylindrical relatively short upstanding walls, drawing hard sheet metal to form the upper part of the pail cylindrical relatively short depending walls, providing an opening in said top of a diameter not exceeding half that '1 of the pail, abutting the edges of the walls of the two parts, holding the pail parts with their edges .in registering engagement with ,a first supporting means adapted to provide the support necessary during welding, butt-welding the parts together at the abutting edges, engaging asecond supporting member, this member being collapsible and having .a hard engaging surface, with the inner portion of the welded seam throughout substantially its entire peripheral length and rolling the welded seam with'high rolling pressure and a low number of rerolling traverses to avoid substantial hardening and to thereby make the seam thickness substantially uniform with that of the walls oneither side.

7. A'method of the character claimed in claim 6 wherein the collapsible supporting member has a hard steel engaging surface and the rolling is effected by pressure applied at three spaced points on the outside of the seam.

8. A method of makingmilker pails of the suspended type, comprising drawing hard sheet metal to form the lowerpart of the pail .withan imperforate bottom and generally cylindrical relatively short upstanding walls, drawing hard sheet metal to form the upper part of the pail with a top and generally cylindrical relatively short depending walls, providing an offset opening' in said top, abutting the edges .of the walls of the two parts, holding the pail parts with their edges in registering engagement witha first supporting means adapted to provide the support necessary during welding, butt-welding the partstogether at the abutting edges, engaging a second supporting member, this member .being collapsible .and having a hard engaging surface, with the inner portion of the welded seam throughout substantially its entire peripheral length and rolling the welded seam with high rolling pressure and a ,low number of .rerolling traverses to avoid substantial hardening and to thereby make the seam thickness substantially uniform with that of the wallson either side.

FERNAND J. J. J. HENRARD.

"REFERENCES CITED The following references are of record in the file of this patent:

UNITED I STATES PATENTS FOREIGN PATENTS Country Date Great Britain Apr. 12, .1939

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